Codes needed for breakers gearbox

[Kellen]

Im struggling to know if breakers gearbox will fit my van as my Fifth gear has gone and 1st is ceasing 
Its a Berlingo 625 HDI Diesel 2011 
Citroen dealership parts told me these codes 
Marking DP48 
BE4R type
Nothing at local Breakers for a month ... so using eBay ... but struggling to know correct part to buy and get delivered 
My mechanic will fit plus new clutch when i get it
Is there more info needed or more codes that are suitable for it?
Some breakers say only need van reg others say i got to get a code off current gearbox somehow! Its confusing and im burning the diesel as its my works van 

Is there a better site other than eBay- advice appreciated

[Gryffindor]

catcar.com - I believe you can enter your reg and get specific details on all parts fitted.

[cancunia]

You'll need your VIN..

http://catcar.info/citroen/?lang=en