I think that the price is a bit high but not silly. I've looked into the getting these from a US seller, they were $100 per fish but since I'm in the UK it would be nearer double after shipping, handling etc.
If you want a similar alternative then the 'standard' royal, Panaque nigrolineatus/L190 is essentially the same and a fraction of the cost. But if you are like me, being 'essentially the same' isn't enough.