Answer: Clematis recta grows between two and four feet tall and wide, it tends to spread outward unless supported somewhat in the center to help with the height.
It is not currently included in the online plant listing for Monrovia, however the stores that sell Monrovia plants are independent retailers and so may still offer it. (Monrovia is a wholesale-only nursery and does not sell retail by catalog or internet.) You would need to check directly with them and see if they have this plant or could obtain it for you; also, keep in mind selections tend to be wider in the spring than at this time of year.
There is a zip code based dealer locator at the Monrovia web site to help with contact information.
Best of luck with your search!
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