You'll be very lucky "our kid" to find that. Watched a 60 and a 62, 64, 66 go through the bay last year but the seller only had what he had of these very rare "above 56" types. They also are 144bcd )A for strength, and B) because the era they where around in was predominantly Campagnolo 144bcd era. I ride a Campagnolo 56t sometimes and it takes some doing. I'll keep my eyes peeled for you, but I doubt 1 will turn up soon, and certainly wont be cheap. I'll PM you if I find anything, yours Laz.
Edit: Here's another thought for you : " Will the Shimano ? 130bcd crank arms take the strain of even trying to run a 61 ?" The Campagnolo Pista crank arms used to power these monster chainrings where specially designed for the stresses of high toothed track stuff. I'd suggest thinking about changing the cranks to Campagnolo 135bcd Pista (C-Record era)OR ideally Campagnolo 144bcd SuperRecord/Pista cranks. At least if 1 turns up you'll have chance of getting it onto a crank arm designed for its use. Best of luck, yours Laz.