Can you reconsider making the new purchasable corpses able to be Desecrated? There is a risk of losing your Spectre by just weapon swapping accidentally, corpse getting eaten by a trigger, etc.
We have a solution to this issue that will prevent Spectres from being lost in Hideouts/Town due to changing items around etc. If you leave town in a way that would cause you to lose your Spectres, they will spawn on the ground around you in the next area you enter. If you lose your Spectre in any way in a hideout, it will spawn as a corpse on the ground. If a corpse is spawned this way, only the owner of the corpse will be able to use Raise Spectre on it.