After a long search I went for these
https://www.jegs.com/i/Mr-Gasket/720/6860G/10002/-1
Mr Gasket Fabricated Aluminum Valve Covers 1964-1991 Small Block Chrysler 273-360
Part Number: 720-6860G From JEGS Warning don't buy them

These were only fitted in May this year and done less than a 1000mls , all the screws were too long bottoming out in the head, also had to work on the mounting surfaces to to make them flat. That I can deal with for cheap cheesiness covers.
But whats done me is the cracks in the welding around the screw holes on the top, causing a small but annoying oil leak.
Contacted JEGS via live chat with JEGS Only to be told you only get a
3 MONTH WARRANTY ON FAULTS AND MANUFACTURING .

So with taxes and shipping that's £300 i aint getting back, they look great but be warned stay away from these.