Welcome to the forum. It looks like you have a 1970 CB750 K0 with build date of 12/69. I think the value would depend on condition, mileage, and how close it is to original. Having original parts like unstamped 4 into 4 exhaust, wrinkle tank, rolled rear rim, ducktail seat, original paint scheme, double cut fender, 2-hole rear hub, etc add more value. I have seen prices anywhere form $4,000-$12,000. Hope this helps. Post some pictures when you have time.
Cheers