Wunderlich makes a similar product, slightly bigger which also covers the lower most pipe on the frame. Wunderlich is generally cheaper than TT (in MY experience - others may have a different opinion). I have found that TT real prices in SA (comparing Rand price) are about double those in Europe whereas the Wunderlich prices are about 2/3 more (66% instead of 100% more).
All things considered, it basically remains a piece of moulded plastic, albeit high quality. But is does look cool. Actually, most of the TT and Wunderlich add-ons are quite cool looking of a very high quality, both in terms of function and look. There are those who say that all it does is to add weight but actually the parts are mostly very light. TT makes a nice bashplate, especially the longer one that extends right to the rear wheel. Pricey but nice looking, well shaped and fitted and easy to deal with during services.
But to answer your question - I am not aware of anything else apart from those I mentioned above.
Somewhere in the pooratech thread I mentioned the plastic cable trunking (helical) that I used to cover the horizontal strut on the main stand. It is a cheap option to protect it from road rash caused by the front wheel. It will work well on the frame too and it is very discreet. However, you will still need to find a solution for the centre piece.
Both TT and Wunderlich (and others) make a product that covers the centre only. Perhaps cheaper than cover pictured above (I am not sure) but still disproportionately expensive in SA. They come in sets whereas the covers mentioned above you have to buy seperate for each side. Just when you think it is very pricey, you discover you are only halfway there
