We determine quark mass dependent order a improvement terms of the form b(j)am for nonsinglet scalar, pseudoscalar, vector and axialvector currents using correlators in coordinate space on a set of Coordinated Lattice Simulations ensembles. These have been generated employing nonperturbatively improved Wilson fermions and the tree-level Luher-Weisz gauge action at beta = 3.4, 3.46, 3.55 and 3.7, corresponding to lattice spacings ranging from a approximate to 0.085 fm down to 0.05 fm. In the N-f = 2 + 1 flavor theory two types of improvement coefficients exist: b(J), proportional to nonsinglet quark mass combinations, and (b) over bar (J) (or (b) over tilde (J)), proportional to the trace of the quark mass matrix. Combining our nonperturbative determinations with perturbative results, we quote Pade approximants parametrizing the b(J) improvement coefficients within the above window of lattice spacings. We also give preliminary results for (b) over tilde (J) at beta = 3.4.