Rather odd question, don't you think? What matters is if you consider it being a good price and if you think that you got it cheap or expensive?
Personally I think that you paid what I consider should be a rather normal price on a Blizzard 1230, especially since they are not rare in any way (I think, can't say for sure though, that they are one of the most sold acceleratorcars for the Amiga) however you haven't stated wether or not MMU and FPU are included, and/or if you have a SCSI kit (I don't really get what you are trying to say with that SCSI cable)... which of course would alter the price a little bit, as would the memory.
