Trying to solve first mage problems

Greetings my learned friends,

So recently in our 'campaign' our merry band has recently come into a spot of good fortune, and my first order of business (after getting a suitably fine set of armour and sword made for my reliable bodyguard) is obtaining some formulas for the creation of potions for our Witch and myself (under suitable supervision of course).

One of the more important formulas (Potion of Heroism) called for the heart of champions as the key ingredient and thinking about it the logistics...caused me some slight consternation I'm ashamed to admit (and I imagine other 'ingredients' will have similar problems). Firstly I've managed to procure some waterproof sacks (and plan to wash any ingredients down with water after....extraction) as a short term means, but the fact that it will take a non-trivial amount of said ingredient with enough magical power means I will likely be having to hold on to them for a longer duration of time then I'd like.

Thusly, I need to find someway to preserve said ingredients for later use without them 'losing' their potency to the inevitable march of time. I initally thought formaldehyde or some similar liquid might be best, but it might interfere with the potion brewing process, as one experiment in the dark gone awry in Mage's College should tell you. So of course I thought of the next thing, refrigeration!

Initially, I thought the best option would be a custom spell that Summons a Frost Dragon for an indefinite period of time would be perfect, they have a frost aura which I'm assuming should effectively be similar to slightly sub-zero temperatures! Unfortunately, as far as I can tell, you can't Summon a young Frost Dragon which posses Elemental Aura ability until it has at least matured to an Adult which places it beyond the bounds of any reasonable spell, into the realms of Rituals. If one could procure a much younger Frost Dragon that also had the Elemental Aura ability, this route would be perfect (and such a youthful Dragon would be absolutely adorable as well). 

Alas, the Summoning route seems to be a bust! Next I researched perhaps using a Blast spell and at first it appeared to be going great! Given I only required the merest of damage, it seemed easy to be able to create a spell that suited my task. But alas, I was once again thwarted when it came time for the creating a spell with sufficient duration. The longest one can maintain a Blast spell is with constant concentration. I couldn't simply spend all my time maintaining this refrigeration, doing nothing every day is for peasants as you all of course know!

Looking into ways to extend said spell, I could only come across two, both prohibitively expensive for my meagre windfall. The first would be to create a magic item, but even though the power of the spell I'd be creating would be tiny, I'd still need at least 25,000gp to create an item that suits my needs. Or I'd actually be spending around 87,500gp to create it, as senior mages do tend towards the...more entitled people in this world. And it would take over 3 months to complete. Obviously this option is not acceptable!

The second option would be to cast Permanency on the spell, but unfortunately though that would require a much smaller cost for the ritual itself, the cost of hiring a mage of sufficient experience for 2 months would easily offset that. 

Pray, help me my learned friends, is there a balm to soothe my ill? Perhaps an obscure creature or an ancient grimoire that I have overlooked?

Awaiting with sincere hope,

Nimas, Magister Third Class

P.s. Please don't suggest I simply buy ice from whatever local "Ice House" is in the area. What do you take me for? A non-magic weilding peasant?

The new book, Lairs and Encounters, has a good few detailed rules for gathering monster parts and how to preserve them. It introduces a speical ceramic jar that does the job. I wouldn't want to spoil anything else, the book is worth the buy when it comes out. But knowing there is a simple/more mundane fix than creating a custom spell for it should help you balance what you decided to do in the future.