Re: best way to get 5os Foh stick?
As a general rule for this sort of thing, you need to find a socketed (grey) scepter with the appropriate staffmods, or find a scepter with the right staffmods and check how many holes Larzuk's going to punch into it.
Remember that even if Larzuk could give more than 2 sockets to a magic item (which he can't), you still can't make a runeword in magic items. In this case I guess you'll stuff it with light facets, and if you can afford light facets you probably know this already. There you have it, anyway.