The Penn Museum online Collection is small but nice for the anyone looking to see Roman lighting and glass. They have a nice example of a glass stopper! This should give you the documentation for a similar stopper. There is an example of pressed glass in the mediterranean collection, and several blown glass flasks and pitchers, which look modern and elegant, and as they are very early A.D./C.E., it could be argued that similar pieces were likely possible throughout our SCA period, at least for the Eastern Roman Empire.
Also useful and interesting is their collection of oil lamps. I had not seen an oil lamp with the wider end curved up. The other examples had tiny molded handles but not all pierced. One interesting bronze version is also present. Something I like is at least one had a comment on the method by which it was made.
These items ranged in date from the 1st century through the 5th as far as I took note in my quick viewing. Quite nice, definitely another museum to keep on a list of places to visit and online collections to check when thinking early period glass and lighting.
I didn’t have time to explore the online collection any further before posting– so if you spot something particularly nice in their online collection, do mention it in a comment.