There are certainly more informed opinions than my own available from this forum. However, I would say that based upon lead times from domestic manufacturers that the market could certainly support another player. That said, I think your challenge will be selling "hand built" as an advantage, particularly if there will be a pricing variance. I would assume that you would have an advantage in terms of being able to customize specific units. Based on your stated experience I would assume that you could build a quality unit. Now, where is your competitive advantage over the current producers? If you're in my region, it could be the ability to service your products. It may be a short lead time for experiemental sized units. Maybe you truely can make equivalant size/quality for less.
One advantage you have is that you already have a stable business that can survive even if the still market is a slow climb. You also should have a good handle on your costs, and this site is a great investigative tool to figure out the pricepoints and lead times that are currently in the market. It also shouldn't be difficult to estimate the costs you mention from dealing with overseas producers - even the harder to quantify (travel, language barriers, exchange rate fluctuation, time zone differences, etc.). So in a very general sense, I believe that a domestic manufacturer would be welcomed with open arms. Whether your business can expand to be that manufacturer is dependant upon your ability to meet the current pricing of the established manufacturers, or clearly demonstrate value for any additional costs.
Hope that helped a little, and welcome aboard.