The 5960/7316 are 12AU7 variants. The SP10 doesn't use any 12AU7 tubes. The tube complement in a SP10 is: (4) 6922 LN, (8) 6922, (2) 5881, (1) 12AT7.
You "might" be able to sub that for the 12AT7, but the circuit wasn't designed for that tube.
You "might" be able to sub that for the 12AT7, but the circuit wasn't designed for that tube.