If you are eligible to buy a firearm and your friend is also eligible, then why doesn't your friend buy the firearm while you are unavailable, register in his/her name, thus 'owning' the firearm.
Upon your return, your friend sells said firearm to you; provided you meet all the legal requirements to own, you register under your name, problem solved.
That is if your friend doesnt decide that they like the gun and tells you to go get your own.

You would not provide any cash to the friend in this transaction, therefore, no straw purchase, or whatever you would call it.
My $.02.
Why not just wait? IMHO it is better to see what you want in person anyway.