Here is a website I have saved that have a lot of hardbags and trunks. The "Strong" version is supposed to fit your Spirit according to their site. Good looking bags and probably not more than the used factory bags in price. They even have the side rails to fit. I'm short on time and did not check into the dimensions or volume of them, so you may want to do that.
http://www.tsukayu.com/

When using the T bags, one thing to consider is the exhaust clearances. The Spirit has a double stacked exhaust that sits a little higher up than the T's dual set up.

Stan

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Current love; 2004 GL1800 CSC Cobra trike (silver/white).
Past love; 1999 Ace Tourer (Silver over Black)

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