If you search for MS25036-153 on our website nothing will come up. This is because this is a military specification number not a part number. We carry several parts from TE Connectivity AMP Connectors that meet these specifications according to the TE website (seen below). Please review the datasheets and choose the one that best suits your application.
RNF-100-1/2-BK-STK TE Connectivity Raychem Cable Protection | Cables, Wires - Management | DigiKey
RNF-100-1/2-BK-FSP TE Connectivity Raychem Cable Protection | Cables, Wires - Management | DigiKey
RNF-100-1/2-BK-FSP TE Connectivity Raychem Cable Protection | Cables, Wires - Management | DigiKey
Heat Shrink Tubing | Electronic Components Distributor DigiKey
Also please note military specifications for DigiKey products are for reference only, which means the product is manufactured to military specifications, but will not have the paperwork that verifies the certification. DigiKey is unable to provide any military documentation or certifications regarding military use of its products.