Can only help with 1 part of your question.
Years?
1stGen - Series 1 - 1978-1980
1stGen - Series 2 - 1981-1983 (870 1st Gen)
1stGen - Series 3 - 1984-1985
2ndGen - Series 4 - 1986 - 1988 (780)
2ndGen - Series 5 - 1989 - 1991 (1365)
3rdGen - Series 6 - 1992 - 1995
3rdGen - Series 7 - 1996 - 1998 (483 3rd Gen)
3rdGen - Series 8 - 1999 - 2002
Need more?
12A
The first engine used in the Rx7, with two 578cc rotors. Will give 150 BHP with decent twin carbs.
13B
Introduced in 1983, and used throught the 2nd gen model series. This engine has several variants, including additional intake ports and turbo versions.
13B-REW
Still using the basic 13B engine, REW is a japanese abreviation for Rotary Engine Twin (turbo). All the 3rd gen Rx7's to date have been Twin Turbo (unlike the TurboII 2nd Gen).
20B
This is a 3-rotor version of the 13B engine, only made for the Japanese market.

I had an Infini when I was living in Melbourne. Guess how much? AU$5800/- That's right! And I don't mean downpayment either
