A pair of 12ax7s that were supposed to be the same, but are slightly different; can I use them in my amp?

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I got a pair of RCA 12ax7 black ribbed plates. They were supposed to be identical to be used as a pair, but they are obviously not. Though they they both have the same black ripped plates, the getters are slightly different. They both have D shaped getters, but they are slightly different sizes; one is clearly bigger than the other. Additionally, the silver getter flash or patch covers the entire top of the tube on one tube, but only covers half of the top on the other tube.
Other than those two differences, they look identical to my eyes in structure, size, color, etc. Considering that the shape of the getter is the same, but the size of the getter is not, and considering that the getter flash or patch covers one tube but only halff on the other tube, is there any way that one could say these are still a pair of the same tube? Although these were quite inexpensive (you get what you pay for), I'd still like to contact the seller with the problem, but don't want to claim that he gave me the wrong tubes if they can be considered an identical pair of a 12ax7. The seller has been a great person to deal with for other purchases, and he never claimed he was selling matching tubes regarding their measurments, but did claim he was selling a pair of the same tube make, brand, model, type, however you want to phrase it.
More importantly, are they close enough in structure that they can be used as a pair? I wanted to use them for my input/driver tubes on my Music Reference RM-10 amplifier, but concerned that I might be creating a problem if I'm using two different types of tubes. Can I use them or am I asking for trouble.

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Topic - A pair of 12ax7s that were supposed to be the same, but are slightly different; can I use them in my amp? - hartwerger 13:50:52 02/23/07 (8)

Re: A pair of 12ax7s that were supposed to be the same, but are slightly different; can I use them in my amp? - Vinylforever 18:23:48 02/23/07 (0)

They should be fine ... - PureAudio 17:45:37 02/23/07 (2)

Funny joke. - hartwerger 18:03:26 02/23/07 (1)

Thanks. Not much to do but laugh about it. They're usually .... - PureAudio 20:43:20 02/23/07 (0)

what is important is - REL54 15:38:18 02/23/07 (0)

Re: A pair of 12ax7s that were supposed to be the same, but are slightly different; can I use them in my amp? - Sherlock 14:00:57 02/23/07 (2)

Thanks. Quite logical. Elementary, you might say. -nt- - hartwerger 17:57:04 02/23/07 (1)

; ) Good one! * - PureAudio 20:48:00 02/23/07 (0)

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