what a shame m - I'm a big fan of Walsh - and from what you're saying I take it that you no longer this piece - did you have the lid?
As Dave has commented, this particular method of repair is not uncommon on ceramics - plates in particular, and I've seen it on glass perhaps on only two or three occasions ever, and I'd agree that hand drilling was probably the only way of making the holes for the period that most were repaired. They must have been skilled in producing just the right tension with these rivets, as mostly there is an absence of glue. Hope Dave doesn't object to me showing a tankard of mine, with similar repair - there are eight rivets in total, and I guess that in view of the method of applying the 'strap handle', the style of decoration, and the snapped pontil, that this piece dates from around 1840 - 1870 - probably Bohemian or German I think. I really only bought it for the copper wheel engraving - especially the bird in the cage effect. It may be that rivets were applied before the thing disintegrated, although can't say when - and assume they were made from a non-ferrous material, otherwise rusty rivets would not prolong usability for very long. Unsure of the capacity - think I'd rather not fill with water as it looks a bit iffy, and might not take the internal pressure.
I guess that with weights the depth of rivet is not so critical, but with ceramics and glass vessels it seems to be the case that frequently the rivets do not protrude the full thickness of the glass. On this tankard, only half of the rivets extend to the inside. Do yours stop before reaching the inside m??