Auto Meter Guage Cluster.. why so expensive?

They are expensive because that is what people are willing to pay. The cost to make a product has nothing to do with the selling price. It's priced based on competition and what the market will bear. Personally, I went with a white face guage overlay and put my money it trying to go faster.
 
i love to have A/M cluster, but for 400bucks, I'll be fine with my 25 bucks Makoto gauge overlay....

here is my 25 bucks Makoto kit. And night

not bad for 25 bucks.
Auto meter Cluster <- I want one! I want one!!! I want one!!!!!!!!!!!