What was expensive in the U.S. might not have been expensive in Japan, that's why early Marantz was designed in the U.S. but made in Japan.
The experience I had with Japanese interchangeable parts were, the Japanese made sure that they made every little parts different in the same series, so you had to go to them to get the right parts, that's business.
Well, that's complete BS. I have several brands of TTs from Japan that have many inter-changeable parts. Many Technics tables are like that, as my SL-Q2 has a dust cover from a belt drive SL-220. Other then the badge on the top, they are the same. My Sony's are also exact from the PS-X5 and the PS-X7 and I have seen many other table brands that have interchangeable covers, my PS-X7's cover was broken and it has one from a PS-X30. I paid $30 for it, shipped and it's like brand new.
My advise to people looking for dust covers is to check for like series of tables. You maybe lucky enough to find a match and not have to pay $90 for it like the guy on eBay charges and these are fabricated covers that are made to fit, but not like the original molded covers.
You do have to check for size, but you may get lucky. Why Marantz made even their same series of tables (finding out later) different, is anybody's guess.
W