LMS 3.0 is very old. Even LMS 4.0 is no longer sold new as a separate product or even as an LMS only upgrade. However it can still be acquired as part of a PI 2.x upgrade.
With LMS 3.0, Cisco did not offer a support contract with major release upgrade entitlement. So you need to purchase the upgrade part numbers for PI 2.x. Those will include an equivalent number of LMS 4.x licenses.
Your partner can order using the following procedure in CCW (Cisco's ordering tool):
1.Start with the TOP-LEVEL LMS to PI migration part number: R-L-PI2X-U-K9 (QTY. = 1)
2.Select the BASE LICENSE part number: L-PI2X-BASE (QTY. = 1)
3.Select the SOFTWARE part number R-PI22-SW-K9 (QTY. = 1)
Then purchase migration licenses totaling (for example - 3600) device licenses.
1.Select LMS to PI MIGRATION LICENSE part number(s): L-L-PI2X-xxx-U
a.L-L-PI2X-100-U (QTY. = 1)
b.L-L-PI2X-500-U (QTY. = 1)
c.L-L-PI2X-1K-U (QTY. = 3)