Not quite. There were 700 64-Bit Editions for the £340 tier, plus an additional 45 units included in the higher tiers. In total, 745 units were offered in the Yooka-Laylee Kickstarter campaign. Which, if we count the £675 and higher tiers, leaves us with only 93 units remaining. That's assuming if they already would've obtained the N64 cartridges in the event that 745 backers would have pledged for it. Not waiting till the Kickstarter ends, and then go finding the required amount of carts that were sold. Leaving nothing left to be sold as merch items.
You said in your previous post; "I don't know how they're going about having the carts they sourced turned into flash drives". Thus, I presumed you didn't know that they would outsource it to another company who's converting those carts into flash drives. Heh, I agree that finding 745 mint N64 cartridges would've been a pain in the arse for Playtonic.