LSA 1905 with "P" prefix?

[telperion]

Hi all,

I have been offered this SMLE Mk I***, made by LSA in 1905. The serial reads "P 2XXXX".
(Have just the pix from the ad and couldn't do others. Could have a look at the Old Lady, though). The stock disc reads "18 W.Y".
The finish and all seem to be authentic. No traces of renumbering.

Shouldn't a LSA Mk I have a "K"-prefix, though?

What do you think?

regards and thanks!

T