"fairly sufficient" is a correct and usable phrase in written English.
It is often used to indicate that something is enough to accomplish a task or goal, but not necessarily more than enough. For example: "The budget for the project was fairly sufficient to cover the costs."
"If life expectancy is increasing, then pension ages should rise, but it has to be done fairly, with sufficient notice for people to plan," Ms Altmann says.
Cattrall, you surmise, has always been fairly self-sufficient.
By now, Iran is fairly self-sufficient in building shorter-range Scud-type missiles.
We're fairly self-sufficient and normal people, but O.K., we're obsessive about music itself.
At present, only some 5,000 of them are a match for the insurgents; perhaps as many as 12,000 are fairly self-sufficient.
For all these reasons they tend to withdraw into their own world, which is relatively easy, since their numbers are great enough to enable them to form a fairly self-sufficient, self-contained community.
Andresen seems fairly certain that sufficient consensus will be reached, at least to preclude diverging ledgers.
This assumption has been found to be fairly accurate and sufficient for engineering design purposes, especially when the size of the annular gap is small relative to the mean radius of the annulus, which is usually the case for MR dampers.
Although Proposition 2 is fairly abstract, the sufficient condition formulated there can readily be verified, as soon as a specific market model is adopted (see, for instance, Bielecki and Rutkowski (2015) and Nie and Rutkowski (2015,2016a,2017 (published online on 18 April 2017)).
To account for the clustering of persistent genes, we showed that the strong selective pressure acting on the function of persistent genes, in a permanent state of flux of genes in bacterial genomes, maintaining their size fairly constant, is sufficient to drive genes clustering.
