Perhaps SeReM, the MATLAB Seismic Modeling Toolbox developed by Dr. Dario Grana can help. There are geostatistical libraries in SeReM that can be used to generate a 3D cube out of 2D seismic lines, by using each seismic trace in the 2D line as a vertical dataset to interpolate using kriging sample-by sample.
Perhaps you can also interpolate any horizons you have interpreted on the 2D lines to create 3D horizons that can be used to perform some co-located co-kriging with the 2D seismic traces, in case it enhances the interpolation process to make it more geologically conformable.
Here is a link to the SeReM libraries you can download from GitHub: GitHub - seismicreservoirmodeling/SeReM: Seismic Reservoir Modeling package
Chris
