I was thinking of pairing these two since I don't have a rail.  Would this work or mess up the sight very much if I use it with a 1-4 optic?  How would the weight feel?

http://www.amazon.com/gp/product/B0077RHY6W/ref=ox_sc_act_title_3?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
https://www.botach.com/kley-zion-ar15-m16-front-sight-posts-mount/

That giant bezel diameter might obscure your FSP. I know you mentioned you dont have a rail, but what exactly DO you have? Just the normal glacier grips? There are many cost effective options to swap out. The new magpul handguards look pretty slick for non FF handguards and you can put the accessory rail on it for the light and be GTG.
UTG also makes some inexpensive handguards that are fairly durable.

ETA - Are you dead set on the TLR1 HL?
What are your requirements in a light? The Surefire X300U and TLR1 both have decent output, but I have never seen the light you're wanting in action to be able to compare. I do know in a dark room though, both the TLR1 and X300U will give you pretty decent peripheral light to see targets.

Topic Moved

You would have some of your FOV obscured, but it could still work..  The HPL is not a very well-designed WML.  Obscure less with a standard TLR-1 HL.