As a passionate gardener I'm dying to know what tool you are making!
Anyhow...when you say "take the plunge" and get bigger does that mean giving up the business you now have to take up the manufacturing of this yourselves?
Or are you looking to new markets to sell into - or perhaps looking for retail outlets?
Or are you looking to create an online presence? Or are you looking to outsourcing your manufacturing?
Just a word of warning about the latter.
There was once a wonderful product sold which had been hand-made by a gardening couple. For a couple of years we'd see it at farmer's markets, various gardens in the Open Garden Scheme that the ABC runs, and advertised in the back section of all the gardening magazines which are devoured by garden devotees just as much as the articles.
And then suddenly they disappeared. When we followed up what had happened apparently they had got to the point where they needed to "take the plunge" and make it their full time business and they outsourced the manufacturing of their product to China.
Everything went downhill. The point they had missed - somehow - was that other gardeners really liked the fact that it was a hand made product that they were buying and were willing to pay the price.
So, understanding your buyers is a big key to future success.
Good luck and I hope you keep posting on your decision making.