Equipment is very personal Greg, so I would never make a recommendation. But if you are willing to look at the off brand market, little tubers are going pretty cheap.

If you are willing to look at the used market, $300 will get you a brand name tube amp at pretty fair power. That comes in handy if one of your friends has a drum kit. So you might want to think about that.

This pic is my Fender Hot Rod Deluxe IV, which I just picked up for $969 CAD new. But on the used market around here, the III can be had for $400. So if you are in the US, a $300 budget is certainly workable for a brand name tube amp with some serious poke. But I've never seen Bluetooth in an amp like this. They might be out there, I just haven't seen them.

I love looking around for gear. Do some research, think about what you want to do with it** and good luck. Let us know what you get.

** If you want to run pedals, get something with an effects loop.