Cardboard tubes, suitable for mailing tubes. (Summertown OX2)

Help me find a reuse for these items as mailing or poster tubes. Originally supplied to me & designed as a pump for an inflatable mattress, (& its replacement), each pump consists of one tube that fits inside the other. Approx 48 cm long x 10 cm wide. 2 sets available , meaning 4 tubes. Supplied to me by a private company having been prescribed by the Nuffield Orthopaedic Hospital in Oxford. Neither the co. nor the hospital want them back.