Hi Dave,
We have the same tender and bought a Suzuki 2.5hp (have to match the engines :wink: ) without realizing we "need" the long shaft. The Suzuki is a short-shaft (15") and has worked fine for two seasons. If there were no weight in the back, the short shaft would be a problem but with the weight of the helmsperson in the back steering the tiller, it works fine. We use ours just to get around the marina or while on the hook and the 2.5hp is plenty. The Suzi is real light and easy to load on and off. We like it.
But if the shaft length is important to you, I believe the other outboard brands do have the long shaft in that horsepower range. BTW, that Alaska Series Tender is well-made and tough as nails. Believe me, I know.