The original part number for the head gasket is 291301, which has been superseded to 27463. Should be available through your local Briggs dealer or repair shop. If not it can be ordered from Jacks Small Engines for about $5.00.
That is the type of pulley starter I would expect on my engine, not the recoil starter, just makes me wonder if it's correct.
Silver, maybe this manual will help you out.
http://www.briggsandstratton.com/la.../Antique Manuals FAQ 2/Model 6BS-domestic.pdf