Assuming that Silvaire is referring to a Silvaire his costs are not out of order. In the UK ours are around £195.
What you need for the annual on a Silvaire is a relatively short list:-
Oil filter
Fuel filter
Air filter
Oil
Rocker gaskets
During the course of the annual you may find bits that need replacement but they are not part of the cost of the annual, they are items that, if you have your wits about you would be found and fixed during the year.
The vast bulk of the cost is in time, not materials. We usually have 3 people doing it over 3 days, including the test flight. It involves removal of prop and cowlings, all fairings and inspection panels and the seats. A thorough clean and inspection, inspections required by AD's, a compression check and lubrication of hinges. Some might think 9 man days is excessive for something that's basically a glider with an engine nailed on the front but it's an old aeroplane and we like to be thorough.