Do it yourself light seals
YES FOLKS, YOU CAN DO IT YOURSELF FOR PENNIES......
OK, now seriously. Its easy and does not require any special material or extraoridnary skill. Here's how..... Go to your favorite art supply store (Wallmart) and get a 12" square sheet of felt. It cost about 35 cents and comes in many colors in the rack. Any color will work, I like to use green because it looks great and easy to tell that the deed has been done. in the next isle, look for some black yarn. Don't get the string type or the extra fuzzy type, about $1.50. Nearby you will find glue. Look for Duco Cement or vinyl adhesive. Don't use model glue or water based glue. Cost $1.50. The other items you likely already have. Scizzors, razor blade and tiny screwdrivers. Now for the fun part.
Using your assortment of tiny flat blade screwdrivers, gently dig and remove gooey foam remnents from the groove where the back of the camera fits into. Use paint thinner and tissue to keep the blade clean. Check the area where the back is hinged to the camera body also. There is usually a patch of foam there. In some cameras this material is like velvet cloth and if it's in good condition can be left in place.
Now that the groove is clean, snip off a peice of yarn. Dip your tiniest screwdriver in a drop of glue. All you need is a tiny amount on the blade. Put a dab in the bottom groove where the back is hinged and start tucking the yarn in place using another screwdriver. Put another dab of glue in the groove about 1/8 inch from the first and tuck the yarn in the glue. Keep the yarn firm but not pulled tight and work your way across the groove. End with a dab of glue and trim the end of the yarn. Do the top groove the same way, from hinge to latch.
Now cut a peice of felt the size of the patch(s) on the cover and using a few dabs of glue to hold it in place.
Once done, the cover will have a nice firm closure and be light-leak proof.