Full length leg warmers might be a more workable option. Then you can use the same bibbs for a wider range of temperatures and just go from knee warmers to leg warmers or no warmers.

However my Pearl Izumi bibbs with long legs are plenty long for me, but I'm only 87 cm (34.5 in) for my inseam. Haven't had them on in a while so I'd hate to guess whether I thought they could work fine for you.