Check out these Very cool Olds valve covers I have Two sets one set is mostly polished for $200 second set is raw , could be powder coated or simply polished $150 prices do not include UPS or sales tax in CA
These Heavy cast covers will accomdate roller rockers and sell elsswhere for $299 (raw)
this is the original info from the seller ...
Cast aluminum extra tall valve covers with 'Oldsmobile' in script lettering, and Olds rocket emblems fore & aft. Will fit all roller rocker arm systems and the JM-1160 rocker stud girdle. Will not fit under OEM A/C, power steering, power brake or accessory brackets.
(No baffles, outer height 4.750", inner height 4.250", 5 bolt holes but can be drilled for 10, can be ordered with breather holes staggered or straight across.