Following up on another post, I think I'm going to go ahead with the convert from an old 1988 Bianchi Strada (road bike) into a recreational cyclocross by rebuilding the wheels with 650B rims. With the smaller rims, I can increase the tire size from the current max of 25-28mm (depending on model of tire and its specific profile) to fit one of the three tires that I'm considering that are Schwalbe G-One 40-584, Surly Knard 41-584 and Schwalbe Marathon Cross 44-584. Because I have to buy new rims, I might as well ensure that I have the right ones. Surly recommends 23-30mm so likely, the others would be similar except that the G-One offers the option of going tubeless.

Can I have suggestions for economical rims or at least rim brands to consider?

Thanks