original wills are only produced as a last resort - the microfilm has to be unreadable for this to occur or there has to be a legal reason (property conveyance) that the original document is needed. Also many of these wills are in the first batch to be digitised ready for new iCentre opening next year so might not be available;
Yes the library will generally now allow digital photos off microfilm reader screens - as you say very variable - 19th C wills are verbose - at 50p/page copy cost very expensive.
No the museum will not do a copy service - they point you towards paid researchers who will.
There are refs, as you have probably found, to the Fleetwoods in Manx Note Book.