I would just question,,why would LSA put 'L.E. I' on a commercial 'Lee' sporter rifle.

That is a Military rifle designation, nothing to do with a commercial sporter.
If purpose built as a Commercial Sporter, then the 'L.E.I' means nothing as that designation is for an entirely different configuration, that of a Military rifle.
Why would they (LSA) put it there? It would have no meaning and no business being there.
My point being is that the rifle action came from an X-military rifle.
Again just my opinion, but with my reasoning also.
(My commercial BSA MkI* SMLE and CLLE are both simply marked BSA & Co on the sockets dispite being full military configurations. No military markings or proofs. They were for civilian/private sales. Same as the Lee Sporters.)

As I said, I'd like a closer look at the right & left side of the socket to see if anything was done there.
It's not difficult to fill and disguise the volley site cuts.
The engraving seems to be especially placed to do so on both sides.

I'll remain on the fence w/o a closer look to answer some questions.

If a true commercial sporter, especially an LSA mfg, I'd hazzard a guess at value in the $800/1000 range (303 cal) for the condition.
Better condition, w/dust cover and the value goes into the teens easily.
If a sporter built on an x-military by Greener, then a bit less.
All the above considered w/an excellent bore.

Either way, it's a great rifle.