My suggestion is to run each sub's coils in a series and then parallel the two subs together to get a 4 ohm load.
Save yourself some money on an amp that doesn't have to be one ohm stable by simply rewiring.
There's a handful of good amps that meet the 4 ohm @ 1 channel requirement. Try Rockford, JBL, JL, Phoenix Gold, PPI, Crossfire, MTX, Blaupunkt class T and the list goes on and on and on and.......