Zeller's is a deparment store along the lines of Wal-Mart and K-Mart. There's nothing out of the ordinary about it and if you're a tourist, you don't come to Prince Rupert just to come here. But if you have to, Zeller's is your bet to purchase goods.
Some things are definiltey more expensive then others. The food is at average prices but the clothing can be expensive.
If you shop right, you can get quite an assortment of things. I'd say get out 40 dollars in Canadian currency and that should set you.