Contemporary records suggest that when first commissioned Victory carried spare topmasts: quote; April 1778 moored in the Medway spare topmasts and booms taken on board, (but no further details as to location.)
Victorys Fore topmast is 63' long which at Heller scale is 192mm, the waist opening - rail to rail is 144.68mm. which means if carried, a spare Fore topmast would extend forward to at least the Galley chimney.
The athwartships rail at the break of the Foc'sle has a half round recess either side of the Belfry, is this to support the longer spare masts or yards?
Damage reports following Trafalgar refer to jury rigging a Fore topmast using spars .Victorys' boats on the skids were badly damaged and presumably any spare timbers in that location may well have suffered damage also.
At Trafalgar Victory lost her entire Mizen mast, topmasts and yards, gaff and driver boom.
The jib boom was removed and used as a jury mizen mast, she also lost her fore yard, spritsail and flying jib booms.
I have searched my reference books but can find no information regarding spare topmasts or spars in the aftermath of Trafalgar, but it is recorded that spare timber in the form of 48' of 4" thick oak plank was expended to splint or ‘fish' the damaged main mast.
What does this tell us, it is hard to draw conclusions, but in a service notable for accounting for lost items even down to 15 leather buckets, the absence of references to topmast spares is perhaps puzzling and if such spares were carried why was it necessary to remove the jib boom to make a mizen jury mast?
As with everything concerned with this fascinating subject, there are always more questions than answers, and perhaps Steves has a point, will we ever know?