Damaged disk valve! Reed valve conversion?

I believe a damaged disk valve is preventing my 1965 VBB 2M motor from running. The WORB5 and/or the DRT reed valve intake manifolds look like interesting fixes, but I want to preserve the classic look of the scooter. Do either of these parts allow me to use the original engine cowling? Are there additional modifications needed on the engine or frame? If so, what are they? Are there any other parts like gaskets, screws, etc. that need to be ordered in addition for it to match with my SI Carb?

Thanks to all you Vespa Guru’s out there!