Need help from Sportco/Omark 44 owners

Gents,

I am doing a bit of a study on the Sportco/Omark 44 rifles and so far have found some of the generally accepted production dates seem to be off. Hoping to put together a nice small summary

In order to do a decent job, I need more serial numbers of which as of now I have 57 from early 1968 to the 43rd rifle made in 1987.

Could anyone who has access to a rifle with a known purchase history give their data? I do not need the last digit, just the following data:

1) Serial number and prefix
2) If the imprint says Sportco or just the Omark print.
3) If a UK gun, the import proof date (or picture/description of same, I can date from that)
4) If it has the original light barrel (1-12) with handguard, the intermediate weight barrel (full over chamber in 1-13 to circa 1982) or the final Omark/ MAB bull barrel with the 1-14 twist.

Also I have very few serial number post 1984, only 2 out of 57 are MAB made rifles, nothing past 1987 even though MAB seems to have advertised the rifle up until 2008 on their web site (at least parts support)

any help would be appreciated.