You may have discovered this site, but if not, then it is worth visiting:

YouTube - BFI films Channel

Where you will find not only a fair number of archive films with a Scottish interest, but also many others which are worth the effort of having a look at.

At the time of posting, the summary indicates that there are 248 films available, and this may grow over time, so might be worth revisiting, as I read elsewhere that about 1,300 of these films exist (not online, but for visitors to the archive).

A piece of Off Topic and largely irrelevant information, but the physical location of the BFI's store is the former Nuclear Weapons Storage Site for RAF Gaydon in Warwickshire,

http://www.subbrit.org.uk/rsg/sites/g/gaydon/index.html

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