You have a very desireable rifle and quit collectable. Valued at 250.00 plus to Military 22 Trainer or Mossberg collectors.
There is quit a following over on the rimfirecentral.com forums under "Mossberg and Military trainers forums"
On the 1st contract of 6-3-41 of 10,000 rifles the cost to the US Government was 10.00 each and Britian only paid .65 cents under the Lend-Lease program. To the best of my knowledge there are no records as to the cost to Britian on the later contracts as we intered the war Dec. 1941.
But your rifle in the 3-27-42 of 20,000 rifles cost the US Government 13.49 each but no record on how much Englandicon paid. Maybe the whole price since we were at war.
Don't let the rifle get away from you as they are rather rarely seen. A lot of the rifles were not returned to the US after the war. I hope this information is of help to you.
Frank