We report simulation of the conduction band alignment in tensile-strained GaP-enriched barrier structures and experimental results on injection lasing in the green-orange spectral range (558-605 nm) in (AlxGa1-x)(0.5)In0.5P-GaAs diodes containing such barriers. The wafers were grown by metal-organic vapor phase epitaxy side-by-side on (8 1 1)A, (2 1 1)A and (3 2 2)A GaAs substrates, which surface orientations were strongly tilted towards the [ 1 1 1]A direction with respect to the (1 0 0) plane. Four sheets of GaP-rich quantum barrier insertions were applied to suppress the leakage of non-equilibrium electrons from the gain medium. Two types of the gain medium were applied. In one case 4-fold stacked tensile-strained (In, Ga) P insertions were used. Experimental data shows that self-organized vertically-correlated quantum dots (QDs) are formed on (2 1 1)A- and (3 2 2)A-oriented substrates, while corrugated quantum wires are formed on the (8 1 1)A surface. In the other case a short-period superlattice (SPSL) composed of 16-fold stacked quasi-lattice-matched 1.4 nm-thick In0.5Ga0.5P layers separated by 4 nm-thick (Al0.6Ga0.4)(0.5)In0.5P layers was applied. Laser diodes with 4-fold stacked QDs having a threshold current densities of similar to 7-10 kA/cm(2) at room temperature were realized for both (2 1 1)A and (3 2 2)A surface orientations at cavity lengths of similar to 1 mm. Emission wavelength at room temperature was similar to 599-603 nm. Threshold current density for the stimulated emission was as low as similar to 1 kA/cm(2). For (8 1 1)A-grown structures no room temperature lasing was observed. SPSL structures demonstrated lasing only at low temperatures < 200 K. The shortest wavelength (558 nm, 90 K) in combination with the highest operation temperature (150 K) was realized for (3 2 2)A-oriented substrates in agreement with theoretical predictions.