There are a handful of items that emulate (Ring of Evasion) and/or augment (Monk's Robe) class abilities. However, "class ability" isn't one of the effects on the estimating magic item prices table, nor have I been able to find other guidelines for pricing such abilities.
Are there published guidelines (preferably from Paizo/WotC) for pricing magic items that emulate/augment class abilities?
This is specifically for a PF1 campaign, but translating from 3.5 is usually straightforward enough that I'm tagging it, too. If there are contradictory guidelines for the two systems, the PF1 guidance wins out.