NO 4 Mk 1- no serial number?

You guys were a lot of help the last time I had a question on my Enfield, so here's another one to toss at you.

I just recently realized the only place my No 4 Mk 1 has a serial number is on the bolt handle. Nothing I can find at all anywhere on the receiver or the band that comes down from it (between butt stock and fore stock, sorry I don't know the proper name for it).

All I can find is the "ENGLAND" and crown stamp forward of the bolt slot on the right side, "No. 4 Mk. I ROF (F) 10/43" on the left side below the bolt slot, and what looks like a partially stamped arrow on the left strap. No serial number anywhere.

Is that normal for a war-time production? Or am I missing it somewhere?

Without any doubt it has been ground/linished off and 'made good' or it is covered in paint. But you can be rest assured that it left the Fazakerley factory with one. The body is the 'master component' and is the recorded 'weapon'. The problem with Fazakerlet is that the rifle makings were always engraved with what we called a 'scratchy pen' very shallow so it'd pay you to look very carefully

I figured it had to have had one, but wasn't sure where else it might be. Almost everything else appears to be in the "scratchy pen", so maybe it's covered or ground off like you say. I'll have a closer look and see what I can find. Thanks!