In Italian, the conjunctions "ma" ('but') and "e" ('and') can preface imperatives to reinforce them as in: "ma/e vieni!" ('do come!'). Does anyone know of any languages that display this phenomenon as well?
The order is really arbitrary or a result of the syntactic constraints of the language.
(Generally SAE requires imperatives take the first position whereas even in neighbouring Eastern European IE Your food eat! Or Home go! are perfectly normal. Accordingly generally the SAE imperatives do not have unique morphology to make it clear that they are imperatives. So one role of these particles in SAE may just be to mark the imperative, not unlike -le in colloquial Spanish.)
That constraint lifted, one parallel here is to the German "flavouring particles", like doch and ja, when used in an imperative phrase. In Russian there is ну, in Armenian դե, բա and բայց. The former are roughly like English well, the latter is literally but but even more than English though and German doch its position is very free, including in imperatives. In certain contexts Russian и can even be used in imperatives, where it means too or also (Ну и сделай!).
Their function is not exactly just reinforcement, it may even be softening, but that's often the practical effect. (My Italian Sprachgefühl is weak here but it says that in Italian it is not exactly reinforcement either.)
The English Wikipedia article https://en.m.wikipedia.org/wiki/German_modal_particles, like most of the talk on this, implies that flavouring particles are somehow unique to German, but of course, as you and I have shown, it's not. What's relatively unique in modern SAE is freeish word order, which is why they are called "particles" not "conjunctions".
(I would argue that English and in And don't come back! mentioned in comments by Draconis is indeed productive. Productiveness doesn't mean a feature can be used in all situations, just that it can be used in (some) new ones.)