Relatively common with the wheeled ones, though: Centauro B1 and Centauro 2 add up to about 850 built, AMX-10RC (464, being replaced by EBRC), ERC-90 (379, 90mm), VBC-90 (34, 90mm, retired), SIBMAS (Belgium, 90mm, 162 for Malaysia), Pindad Badak (Indonesia, 14, 90mm), (Type 16 (Japan, 142), Rooikat (South Africa, 240, 76mm), Ratel-90 (South Africa, 90mm, ?), PTL-02 (China, 100mm, ? for Myanmar), Type 11/ZTL-11 (China, 105mm, 1,250), PLL-05 (China, 120mm gun-mortar, 500+), Type-07P (China, 120mm gun-mortar, 18+12 for Cameroon and Tanzania), 2S9 Nona (Russia, 120mm gun-mortar, c1,000) and M1128 (142, withdrawn).
For tracked vehicles in the direct fire-support/light tank category, if not all actually IFV based, you've got the TAM-2C (Argentina, 105mm), Type 15/ZT-5 (China, 560+), Type 89 (China, c100 or c230, 120mm, retired 2015), ZTD-05 (China, 830), Zorawar (India, in trials, 354 to 700 required), AMX-10PAC 90 (90mm, 10 for Indonesia) and Harimau (Turkey/Indonesia, 18+8 for Indonesia), 2S25 Sprut-SD (24?), PT-71/PT-76(M) (Russia, modified by Israel, 90mm, Indonesia), BMP-3M (100mm, c1,000) BMD-4M (100mm, 200), PT-85 (North Korea, 85mm, 560 PT-76/PT-85). Plus the now retired Swedish IKV-91 (90mm, 212), the M8 Buford (6, Cancelled) M10 Booker (26?, cancelled), and the remaining hordes of PT-76 (Russia, 76.2mm). In several cases they may not be based on IFVs, but there are IFVs based on them.