Hi Keith - I'd suggest not old. Drinking glasses where there is an absence of ……………. snapped pontil scar, polished pontil depression, lead glass ring, other features which we know to indicate age i.e. colour perhaps, gadget mark on top of the foot, noticeably domed foot or folded foot, collar immediately under bowl, specific cutting, reasonable wear ……………………….. make for difficult dating.
Glasses, even with only reasonable quality, will have something from the above list to help assess age.
My humble opinion suggests these are from somewhere in the last forty to fifty years, and lack quality - so you're branching out into drinking glasses now then

How were they sold to you, or might they have been from a charity shop?
Sorry, what does "small indentation mean"?