So, I have a the carcass of a GK 1001RB ii combo that I got from some friends. 1 or both of the speakers is apparently blown (I haven't gotten around to fully testing yet). Basically these combos are way overpowered as a 2x10. Anyway, they took the head out and put it in a head case which they kept. My plan is to get a 700RB ii head to put in (I have all the hardware, etc... to put it back into the combo) to bring the 8 ohm power output WAY down, and 2 replacement speakers, hopefully that will also be a little more stout than the originals (I suppose ordering OEMs from GK is also an option, but probably expensive and boring). I'm looking for any suggestions on replacement speakers that will work well in the combo. I haven't gotten complete measurements of the internal dimensions, but unless somebody chimes in with them, let's assume roughly .9-1.1 cubic feet per speaker or so and tuned in the 45-60Hz range. So I'm looking for drivers with FS in the 50s or below, extension up to 3-5k (combo has a tweeter which is presumed working), 4mm+ xmax, 150w RMS power handling, and hopefully $100 or less a piece (much more than that and the whole things starts to be cost prohibitive for the final result/value). I have a couple ideas but looking to crowdsource some advice. Also, I'm assuming it will be easier to find 4 ohm drivers than 16. I'm assuming an 8 ohm combined load will look the same to the crossover/amp regardless of whether it's parallel or series wired, but wanted some affirmation of that. Anyway, any help is greatly appreciated!