it most likely peak. So thats around 300 rms per channel. Because its a legacy amp id say aound 250 rms at best so 2 12" alipne type r's should do good in a ported box with around 200w rms going to each.
itll b ok but it wont hit as hard because any L5 i believ is around 600w rms and your amp couldnt supply the power it needs to hit excursion. Youll be giving the kicker around 250w rms which isnt enuff. And hunter is right to about the shivas those are about equal to a alpine but i belive that a aline sounds a litlle better. SOrry for not replying to you earlier my computer screwed up
I agree with basslova here. Id go with 2 12" Alpine R Types. Very good subs SQ and SPL wise. and they run at 300w rms which is about what ur amp will push so they will sound nice...I run two of them myself and I love them.