Stock, depending on the amount of air in the rear tires is 50-60. Mostly, it's right around 55. With those mods, you won't be any faster unless you gear it. I'd say about 70 with gearing.
Money would be more wisely spent on a re-cut head, a pipe, UNI filter, and a port job. That extra 40cc is cool, but it won't put down the power of a ported stock jug.
With a good pipe, filter, head, and port, it should turn close to 80 with the right gearing. It won't make it there like a 450 4T or a higher end 2 stroke will, but it'll do it.