U need to go second hand. Get an amp that pushes about 200 watts into a 8ohm cab and about 400 watts into a 4ohm cab. Get the 8ohm cab first, then, when u can afford it, get a second, equal cab. Giving u 2 cabs with a 4 ohm load, maximizing the output of your amp, and maximizing volume per dollar!
Fender Modern Player Jazz #19