Besides vendors like Mopar Performance, Mancini, Hughes, etc., are there any manufacturers that have OEM sized Magnum intake & exhaust valves in stock and/or in slightly longer lengths? Or any other common applications that could be cut down? Custom valves may be too much. Just checking to see if there are any other reasonable options.

1.92" x 5/16" stem (8mm ?)
1.625" x 5/16" stem (8mm ?)