There are slight differences between manufacturers, even with the same M-B p/n. There's a photo spead somewhere that more/less successfully shows and describes the differences.

I think the manufacturer is identified by a letter or symbol in addition to the p/n; A, F, etc. ET = "einpresstiefe" = offset (literal translation is 'pressed in depth') and should also be listed. It's a good number to have handy if you're looking to get a matched set.

Mine had a yellowish tint that I attributed to discolored lacquer. I used aircraft stripper to get them down to metal, then had them painted and clear coated. Messy work but the end product was worth it. Cheaper than powder coating, but less durable.

Did they have the end caps? If so, that's a huge bonus.