Where can I buy a 42cm wide aluminium ladder?

[YellowHouse]

Hi All - My first post, so hope this is not too off-topic, but I thought roofing experts might be the best to ask.
I have an Easi-Dec conservatory roof ladder which is adequate for most of my needs, except the top section is not long enough for our unusual conservatory.
Easi-Dec supply a longer section but at a ludicrous price for what is little different than a short section of simple aluminium ladder. It's also not quite long enough.
I'm looking for a section of aluminium ladder roughly 3m long but it has to be 42cm wide, give or take a couple of mm. I can then drill the necessary holes and attach the accessories.
If the treads are oriented for shallow angle use, even better.
Got any suggestions?

Thanks

 

[terrypin]

Not sure if this will help but you could try and they have a sale on.

http://www.laddersandscaffoldtowers.co.uk/acatalog/Multi-Purpose-Ladders.html

 

[YellowHouse]

Thanks. I eventually found a reasonably priced one at STS Access. Currently waiting for delivery, but it should do the job.