Your search for "40G-QSFP-LR4" revealed the following:
NEW Dell QSFP-40G-PSM4-LR 2XJHY 40GB BASE-LR4 1310nm SMF 2XJHY QSFP+ Transceiver
SKU: NSN-0835
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW HPE JG661A 40GB BASE-LR4 1310nm SMF LC QSFP+ Transceiver
SKU: NSN-5570
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Juniper JNP-QSFP-4X10GE-IR 40GB BASE-LR4 1310nm SMF QSFP+ Transceiver
SKU: NSN-6362
Condition: New
Shipping: Overnight Options
Warranty: 365 days
NEW Juniper JNP-QSFP-40GE-IR4 40GB BASE-LR4 1310nm SMF LC QSFP+ Transceiver
SKU: NSN-5340
Condition: New
Shipping: Overnight Options
Warranty: 365 days