We investigate an economic readout for depth-of-interaction (DOI) and time-of-flight capable PET detector that consists of an N×N array of crystals whose light outputs at the front- and back-end surfaces are detected by using silicon photomultipliers (SiPM). The N×N SiPMs at the front-end (back-end) of the detector are read by a stripline configured to support discrimination of the row (column) position of the signal-producing crystal, producing only four outputs for the detector. To evaluate this design, we built 4×4 and 8×8 detector modules (DM) by using 3.0×3.0×20 mm3 lutetium-yttrium oxyorthosilicates. The outputs were sampled at 2 GHz and processed offline. For both DMs, crystal discrimination was successful. For the 4×4 (8×8) DM, we obtained a crystal-level energy resolution ranging from 11.3% to 19.3% with an average of 14.1% (9.5% to 21.6% with an average of 13.9%), an average DOI resolution of 2.5 mm (3.1 mm), and a best coincidence resolving time (CRT), measured in coincidence with a single-pixel reference detector with a 302 ps CRT, of 391 ps (603 ps). The CRT deteriorated with the (8×8) DM possibly due to intercrystal scattering.