Mild steel, graphite or even stainless steel will work, just do not use anything galvanised. Guy, it probably was the new Fakerex, you only get the old real borosilicate glass as either old units at flea markets or as garage sale items, I have seen the new ones shatter as well, and the shards are big and nasty, along with also having a significant amount of small glass shards and spalls as well in there, just from placing hot onto a heat resistant counter top holder.
Even the borosilicate glass is workable with a decent MAPP torch, I have repaired a few measuring cylinders with chipped tops by simply using heat to rework the rim to a smooth even shape, and reforming the spout in the hot glass with some pliers before flame polishing it all, then leaving to cool slowly. Soda glass you need to anneal carefully, it will shatter with the heat at the one point, unlike the borosil glass.