I know Fujimi makes F-14B & D kits... but they aren't much cheaper than Haswgawa. In fact they are probably more expensive. Revell/Monogram makes an F-14D kit. I don't know how good it is, but most kits like that seem to come with the old parts too (ie seats and chin pod).
I don't know of any after market engine nozzels in that scale, but if you really need it, I could make a mold of from my Fujimi kit and send you some resin nozzels.