  We present muon spin rotation ($\mu$SR) and susceptibility measurements on
single crystals of isoelectronically doped URu$_{2-x}$T$_x$Si$_2$ (T = Fe, Os)
for doping levels up to 50\%. Zero Field (ZF) $\mu$SR measurements show
long-lived oscillations demonstrating that an antiferromagnetic state exists
down to low doping levels for both Os and Fe dopants. The measurements further
show an increase in the internal field with doping for both Fe and Os.
Comparison of the local moment - hybridization crossover temperature from
susceptibility measurements and our magnetic transition temperature shows that
changes in hybridization, rather than solely chemical pressure, are important
in driving the evolution of magnetic order with doping.
