We have observed short-range photoassociation of LiRb to the two lowest vibrational states of the $d,^3Pi$ potential. These $d,^3Pi$ molecules then spontaneously decay to vibrational levels of the $a^3,Sigma^+$ state with generation rates of $sim10^3$ molecules per second. This is the first observation of many of these $a,^3Sigma^+$ levels. We observe an alternation of the peak heights in the rotational photoassociation spectrum that suggests a $p$-wave shape resonance in the scattering state. Franck-Condon overlap calculations predict that photoassociation to higher vibrational levels of the $d,^3Pi$, in particular the sixth vibrational level, should populate the lowest vibrational level of the $a,^3Sigma^+$ state with a rate as high as $10^4$ molecules per second. These results encourage further work to explain our observed LiRb collisional physics using PECs. This work also motivates an experimental search for short-range photoassociation to other bound molecules, such as the $c,^3Sigma^+$ or $b,^3Pi$, as prospects for preparing ground-state molecules.
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