Firstly, are you sure it’s a Hope 183 disk? AFAIK, Hope only make 183’s, therefore you need a hope ‘H’ adaptor. If it’s an Avid 185 disk then you need the adaptor linked above by andyl, otherwise you can shim the hope ‘H’ or any non-avid 180 adaptor to fit, just make sure the bolts are long enough. Alternatively, buy a standard 180 rotor and a non-avid adaptor (Superstars are fine for a fiver).
The issue with Avid 180 & 185 PM-PM adaptors is that the faces of the adaptor are not flat and they rely on the CPS washers to account for the difference. You can use an Avid caliper & washers with any other manufacturer’s adaptor (as james said), however you can only use the Avid 180 & 185 PM-PM adaptors with Avid calipers & CPS washers.