I differ with the answer given previously.
Primary rate (PRI) is always the same thing. A 2Mb/s bearer, with 64kbps timeslots (up to 32, but only 30 useable for data as the others are for timeing and signalling). Basic rate ISDN is just two of these timeslots and a 16k signalling channel (2B+D). If the ISP cannot provide multiples of 64k then they are not delivering PRI, it is a different service.
Get a price from a ‘real’ telco (BT ?) and you will get a Primary Rate circuit. Note that BT offer a minimum of 6 timeslots on a PRI. You may only need 2x64kbps, then go for a basic rate ISDN (BRI) (I think you can still get this, it is a long time since I had to use one ?)
The distance is nothing to do with the ability to provide the service, unless you are in the middle of nowhere. This is not ADSL, this should be a proper telco service, so it is either able to be provided, or not..
The speed per channel that a service provider can provide is directly affected by the wiring distance between their closest routing facitiliy and your building. 64kbps is possible, but you need to take that information into consideration.