I think that's the Yamaha replacement fork, and it appears to have the circlip/sealed bearing bottom bracket. Lugged frame, though. Must be one of the earlier ones. Then again, it is listed as a '72.

If you can get one of the early frames (threaded bottom bracket), grab it! They're real nice riders, very responsive, and putting on first line period components turns it into one hell of a nice riding bike. I got mine that way, have been putting it back to original Lambert, as much as I can. I watch the overall performance die slightly with every proper original component I add.