GM Code 53 is the paint code for 1995 Competition Yellow. If you look at the RPO listing that is glued to the underside of the console lid, down at the bottom, you should see something like 53U/53L The U stands for Upper and the L for Lower a thropwback to when some C4's were available as two-tone colors. There may be a "real" GM part number for the little touch-up bottle, but the parts counter guy should understand the "53".
The touchup paint should be available from any Chevrolet dealer world-wide with that code and the year, make and model. If you are ordering thru one of the Corvette accessory catalogs, use the 53 number to match to the company's number.