Metal prints are not limited editons. I personally sign them with a silver or gold pen. 
Here are some options for different sizes and prices.
16x16=$150
16x20=$175
16x24=$200
20x20=$200
20x24=$250
20x30=$300
24x36=$450
30x40=$550
 
Once you have finished your order, please CONFIRM YOUR METAL PRINT ORDER WITH TITLE AND SIZE HERE.