Are you fussy about scale?
The old 1/25 scale AMT 70s & 60s Indy kits can be had for a reasonable price. Ebay is full of them.
There are a few 1/24 scale F1 kits out there by Japanese manufacturers, though the pickings are few in this scale. Revell of Germany also did a few 90s F1 kits in this scale, though not as detailed as the Japanese kits.
1/20 scale is where most of the action is in F1 kits. Tamiya and Ebbro are the main players here though there are a few from other makers as well, and there are a fair number of kits from the late 60s and 70s available in this scale. And all of the modern kits seem to be in this scale.
There is also a good number of resin kits on the market, but they certainly can be pricey. And of course the initial resin kit is only the beginning, with additional accessories and decals, etc adding to the total.
Then there are the 1/12 scale kits, but these are costly to buy, as are additional accessories if you chose to add them. Tamiya does a few iconic 70s kits in this scale.
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