When you go looking, take a magnet..... a strong fridge magnetic sticker will do. Look at the base of the pan. If it is a magnetic inlay, be very wary, some do not work very well. Also be wary of cheap laminated bases, the layers can separate under the thermal stress.
The cheapest Chinese flat bottomed woks and pans work well. Zebra and Meyer are reputable, but again, test with a magnet. Ikea do some very good cookware.
I made my own griddle out of ¼" mild steel plate, seasoned with oil and salt, it has lasted 10years of use with no rusting, and cost buttons!