Risk equalization is a fundamental tool in health plan payment in many countries. Data availability often constrains the feasible models. This paper proposes, implements and quantifies the gains of a risk equalization scheme which incorporates risk sharing in a data poor context. Risk sharing relies on total spending data likely available for purposes of payment, potentially increasing feasibility of an effective payment design. To examine incentives for risk selection, alternative models are evaluated in terms of fit at individual, insurer, and group level. Using Chile's private health insurance market as case study, we show that modest amount of risk sharing greatly improves fit even in simple demographic-based risk equalization.Expanding the model's formula to include morbidity-based adjustors and risk sharing redirects compensations at insurer level and reduces opportunity to engage in profitable risk selection at group level. Our emphasis on feasibility may make alternatives proposed attractive to countries facing data-availability constraints.