Five suggestions for you.
First off add a location to your user so people have an idea where you are shipping from (if these are being drop shipped likely best to give that location). And also advertise average shipping cost.
Second DONATE to Pinside - it is the least you can do if you are using their site to advertise
Third give people some idea of shipping cost, material item is made from, etc so they have some kind of a clue what they are buying. Not too much detail just enough so they know they are not buying a piece of carpet.
Fourth Offer some kind of an introductory discount (say &12.50 for first 30 days to get your name other there and create some buzz) Then once you get a few feedbacks go to your regular price.
And lastly offer quantity discount - your best customers will likely want a few of these to cover all their machines not just one!