Then buy it.
I have traded in stuff for jems and never regretted it. The are fantastic. I think that most of us on hear would agree with that
Caution is advisable though. I have given away cheap guitars to friends because I was done with them , and regretted it ever since.
If you want a Jem because it is better than the Peavey which is good but has no magic quality fo you, then fine. If the Peavey has the Mojo, then don't part with it because that is rare.
Yep you are 13, but you know what you want, you'll make the right decision. Just be clear about what you are giving up.