Mystery horses marked MF

This is one of my favourite S Range horses but is a bit of a mystery for two  reasons.

The only code or marking it carries is a small MF on the top of the base. I have seen other horses with  similar markings.

Then also I can't really pin it down to any horse in any of the listings I have.

I wonder if this might be one of the very earliest S Range separate horses, given that the MF code may have been used for the Miniature Figurines 20mm range (Alberken plus later additions) which was the range before the introduction of S Range.

I will try to review the thinking of what came in when with the S Range horses and write it up here later - the story seems to get more complicated all the time.