The sticky re MS Parts in the Marlow-MS section has instructions to get to many MS, Luhrs & Hunter parts. The bad news is it's not searchable so you will have to scan through thumbnail pics to find something that looks similar then open the photo to be sure and view part # and source info.
I have found many applicable parts but it takes some digging.
For late model 34Ts / HTs there us a sesrchable BOM that Ives pic #s to make it easier but I could only get the 34T BOM.
It's unfortunate as there was a lot more MS info avail online but Marlow pulled the sites after MS purchase and they won't even respond to my emails. I would be willing to take on the task to get more posted online somehow but they won't answer so I've given up.
There used to be schematics, manuals, etc available before Marlow got involved.
If you post a picture or 2 in the MS section you have a better chance of someone recognizing them and responding.
I have found a Bomar / Pompanette catalog online that was helpful when I was ordering screens for mine. They were difficult to deal with as I recall they required a model # of the portlight or screen and wouldn't go by dimensions. I finally found the #s in the catalog that matched my dimensions.