Patio cover (lean-to) or conservatory

fifthofwhisky

I'd like to establish if I might be able to find a conservatory style building suitable for a space at the rear of my property. 

I have a small patio adjacent a single storey extension to the property at the rear. The extension roof and guttering overhang the patio approx 20cm. Perpendicular to the property and on the boundary line is a wall on my side of the property, approx 1.8m high, and approx 3m across from the property is a wall approx 90cm high that abuts the boundary wall. The wall bounds a raised patio/garden (there are some steps at the opposite boundary). The length of the area to be covered is approx 3.6m. 

I was thinking to erect a patio cover/lean-to and add some panels to enclose it as much as possible from the elements. I found that off-the-shelf patio cover products are sized (e.g. 4x3m) such that I'd need to cut down the length (which is a possibility). These products do have adjustable legs but the overall depth is approx 3m, meaning the legs would either have to go on the inside of the 90cm wall (meaning I could not easily add panels to enclose the space) or be cut down in height to fit on the 90cm wall (and I'm not sure the box section and fittings used  on these products would allow that).

Hence I'm now thinking that for the potential amount of work and cost I might as well consider a conservatory. I'd need a building approx 2.5m at the high side to 2.2m at the low side, and half-height at the garden side. The side facing out onto the patio (toward the steps) could be full height panel with a doorway. The only 'irregular' section would be the triangular panel which would fit atop the boundary wall as it would need to be let in to accommodate the extension's roof overhang (approx 20cm x20cm cutout).  

Would it be possible to purchase a 'conservatory' product to fit this space? Any recommendations for suppliers, etc. most welcome (I'm based in the West Midlands).