Clive cams in Ferntree Gully can supply a fresh cam with a K grind for $350 if your cam is flat. I've rebuilt my b20e and it's worth going though fcpeuro, bottom end should be fine except the cam damage to bearings. Bottom end bearings on fcpeuro you need to buy the b21/240 parts. They are identical but thier listing's are silly for 140s. Cam bearings and retainer I'd get from p1800 parts, just easy.
I do have a brand new set of fibre timing gears I'd let go of for not much.
Cam followers. Cvi sell them for a good price. Though so do scandix. You can run chev followers but need different length pushrods, I think ipd still do the high rev kit, the fast road cam is not very aggressive despite being slightly bigger than the K cam iirc, it would come with new followers and pushrods if they are using chev parts again.
A Rebuilt with fresh head and warm cam, good compression and with receipts, shown running, should get between 800-1000 easily if there is someone looking at the time.
Using a 2.1 head doesn't tell me much, which cast number is it? The b230ft is the lower compression bottom end so you should be going turbo with it, the 2.1 head is likely to have K jet ports, it's easier to use a 530 head from the b230ft.
What is the stamped number on the "marine" cam?
This list covers more the ohc cams. But it goes over the ohc ones.
http://turbobricks.com/resources.php?content=camspec