You can check the warpage of the disc by setting it down on a flat glass table or any flat surface really and looking at it from the sides. If side 2 plays okay, and not side 1, then maybe it's a problem with side 1 only, and not a warpage issue. Maybe just replace that disc.
As far as a remote, nearly any Pioneer standard LD remote will work. The DVL series of remotes won't. The remotes for the CLD-D406, 504, 505, 604, & 605 will work but not the tray eject button.
Here's the thread that has many of the players remotes listed via an external link:
viewtopic.php?f=23&t=1706If you find a remote in the USA, it can be shipped to you for about $10 US for 1st class package or $18 US for Priority Mail box. Just look for a cheaper one, it will work as good as an expensive one.