The actual BOM will be different between BE6K (which uses specific part numbers) and BE7K which uses normal CUCM parts. In either case it will be Enhanced licences just for phone and associated users. Or we normally recommend CUWL standard if the users want voicemail and other features. To be more specific could you confirm whether it's BE6K or 7K, and the CUCM version.
Edit - for actual BOM it would be worth getting your partner to confirm before ordering.
Its for BE7k and new IP phones 8841 - around 500 and 8832 around 10.
So I need to make an estimate BOM by using SKU for CUWL (this license supports more applications)? But there is no option for add on license. Its for new or upgrade
One more query is 50 CUWL licenses enough for 500 ip phones as each CUWL supports 10 devices?
Each CUWL Standard licence supports one single user, although that user can have up to 10 devices in CUCM. So the question, given that these licences cost money, is how many of your 510 phones will be used by people needed all the features and applications, and how many are just phones that don't need voicemail etc.
For v11 at least, an add-on CUWL order starts with the same top level part but you specify add on as opposed to new or upgrade under "Order Type".