I am in seek of your assistance to find solution to replace the worn velcro on my SureFire M300 Scout Light tape switch that is no longer sticking to my rail. As a point of reference, my tape switch is mounted at the 12 o'clock postion on my rail right behind the integrated front sight.

Any Walmart, Target, Ace Hardware, etc usually sells adhesive Velcro packs that you can cut to any size you need. I've been using them for years and they work great.

Or you can try something from Manta for your tapeswitch.
http://www.manta.us/products.php#!/Micro-Pocket-Switch-Holder-w-Button-BLACK/p/7528892/category=8235673

I believe this will answer your problem. I don't know if it's out yet but it's due to be released soon as it was announced some time ago. I personally can't wait for it. Hopefully it will solve your issue. If it's not out and you cannot wait then I would second the previous posts suggestion of just replacing with new velcro for the time being.  However the T.A.P.S. system is going to be awesome.

http://www.recoilweb.com/tnvcs-t-a-p-s-system-59013.html

Skip the Velcro and get some zip ties.  A lot more sturdy and there's no adhesive to stop working at inopportune moments.  I've personally had horrible luck getting adhesive backed Velcro to reliably stick to picatinny rails.