That is possible, and was common back in the day. Patch 1.10 blocked this, I think, along with restrictions on where you can portal.
As I understand, durimules is OK around here, so saving quest items should be along the same lines. I believe this isn't very far off regular twinking either, and it has definitely been done in the past. Even crafting quest items in 1.07 for the zero level req and vastly overpowered stats.
Cheesy, yes. Part of the game, yes. I don't remember reading a rule prohibiting this, but just to be sure, either re-read the rules, or check with a mod.
@maxicek would be the mod with the final say, I'm pretty sure.
By the way. You're doing exactly what you should be doing: Asking before doing. That helps build trust, which is pretty much the foundation of this entire community. Keep it up!
EDIT: I don't remember if the completion of certain quests will destroy related quest items on characters in game / partied. 1.10+ sure does. 1.09 and earlier is very likely different in some way(s).
Oh, and good luck on your 1.00 journey! Mastering the game in that patch is difficult, but can be extremely rewarding with its sick rares with low lvl req, almost free SoJs, massive goldfind, strength on boots etc.